1. Field of the Invention:
The present invention relates to a crankcase ventilating system for an internal combustion engine.
2. Description of the Prior Art:
Many internal combustion engines have a positive crankcase ventilating system (hereinafter referred to as a "PCV system") for drawing a blow-by gas from the crankcase into the intake manifold. The PCV system includes a regulator valve (hereinafter referred to as a "PCV valve") which operates automatically dependent on the difference between pressures in the crankcase and the intake manifold. A mixture of air drawn into the crankcase and the blow-by gas flows through the PCV valve into the intake manifold from which the mixture and an air-fuel mixture are supplied into a combustion chamber. The PCV system is effective to prevent unburned fuel and moisture in the blow-by gas from being accumulated in the crankcase to guard against unwanted damage which would otherwise be caused to engine oil. The PCV system is normally equipped with an oil trap mechanism for separating oil mist particles from the gas flow so that a mist of engine oil which fills the crankcase during engine operation and also the gas in the crankcase will not flow into the intake manifold to prevent the intake manifold from being smeared by the oil and also to avoid undue consumption of the engine oil. The conventional oil trap mechanism has however proven unsatisfactory and has been unable to separate fuel and moisture from the mixture of oil, fuel, and moisture.